I have a old inground pool with galvanized walls and it has a wide metal lip all the way around. I would like to get rid of the walls and the lip but I'm not sure what's involved and how much its going to cost?? My liner is shot and the walls are rusted through in the corners I'm thinking up grade to concreat or just fix the walls and a new liner?

Depends on if you are in Bolivia or Long Island how much its going to cost.

You have the walls rulled out and sent to the scrapyars.. the lip can be taken out with a bobcat... and you will need enough clean fill dirt to fill the hole and be compacted...

Because ALL of those are variables we can't guess... you are going to have to get several local estimates from contractors.